What does the bean roasting process look like? The secret of coffee flavour

Coffee is one of the most popular beverages in the world, and the variety of flavours and aromas is an area of interest for many coffee drinkers. It is not only the species and place of origin of the coffee that is responsible for this – the processing and roasting of the beans is also important for its final character. Find out what the coffee roasting process looks like, the stages involved and why it is so important on the journey from bean to our cups.

Why is coffee roasting so important?

Coffee cultivation and production involves many stages, of which coffee roasting is one of the most important. What is the reason for this? Raw, green beans are also suitable for making the beverage, but it is much less aromatic and intense in flavour than coffee made from roasted beans. Green coffee contains more than 300 natural aromatic compounds, whereas the number rises to approximately 1,000-1,200 in roasted coffee, due to the pyrolysis and Maillard reaction that takes place.

The coffee production process must be precisely regulated to obtain a product with a specific taste and aroma. In the coffee roasting process, the length of time the beans are roasted and the temperature in the roaster are particularly important. Roasting brings out the sweetness, acidity and bitterness of the beans, and the balance of all these flavour and aroma components depends on these parameters. The storage time of the roasted beans is also important – the best-tasting coffee is one whose beans have been roasted from 3-4 days to about 4 weeks before being ground and made into a beverage.

What does the coffee roasting process look like?

The coffee roasting process can vary depending on the method used. Special ovens are used to roast the beans. In industrial coffee production, mass roasting is managed by automatic systems that limit the temperature and roasting time. Smaller coffee roasters, on the other hand, often use traditional methods such as drum roasters. The process of roasting coffee using them is longer – in industrial roasters the process takes 1-5 minutes, while in drum roasters the process takes up to 15 minutes – but it allows for an even roasting of the rotating beans and produces coffee of the highest quality and with a varied flavour profile. Each roaster may use different, distinctive methods, so that even the same coffee from different producers can differ in flavour and aroma.

In the coffee roasting process, we can distinguish between several stages:

1. Selection and preparation of the beans – it is crucial to select beans of a specific species or blend, of the best quality, from verified sources. The beans should then be thoroughly cleaned.
2. Proper roasting of the coffee – not only is it important to use the right roasters, but also the precise temperature and roasting time.
3. Cooling the beans – after roasting, the beans are cooled with cold air on special cooling trays or screens to quickly reduce their temperature. In industrial roasting processes, cold water is often used for cooling, which reduces the qualities of the coffee.
4. Degassing thecoffee – the beans are left for a period of time to let the excess carbon dioxide produced during roasting escape. It is also possible to pack the coffee in airtight bags fitted with one-sided valves so that the coffee can be gradually degassed over the following days and weeks.

Types of coffee bean roasting

There are usually four types of roasting, which determine the degree of roasting of the coffee. Each has a different flavour profile and is suitable for different preparation methods.

Light roasting

Light roasted coffee is characterised by the lowest degree of roasting. Its beans are roasted at lower temperatures (180-205°C) and are characterised by a light brown colour. There are 3 types of light roasting: Light City, Half City and Cinnamon.

This type of roasting best highlights the natural notes of the bean, especially for the complex flavours of high-quality arabica coffee. The result is a beverage with a delicate, refreshing, fruity flavour and a high caffeine content. The light roasted beans work well with alternative brewing methods such as drip or chemex.

Medium roast

Medium roast coffee is subjected to a temperature of 210-200°C, resulting in darker beans. It is a fairly versatile coffee roasting grade producing beans with a balanced flavour and caffeine content. Medium roast coffee can also come in 3 roasting grades: City, American and Breakfast.

Both a light fruity acidity and a chocolate and nutty sweetness can be perceived in the prepared beverage. The medium-roasted beans are excellent for making coffee in the espresso machine.

Medium dark roast

Roasted at 225-230°C, the beans have a dark brown or almost black colour with an oily layer on their surface. The flavour is dominated by chocolate, nut and caramel notes, with a noticeable bitter aftertaste. The dark roast coffee is intense and full-bodied, perfectly suited for espresso. It contains less caffeine. The dark roast coffee is Full City.

Dark roast

This type of roasting is referred to as full roasting, which occurs at 230-250°C. The process gives the beans an almost black colour with a glossy, oily layer on their surface. The coffee has a pronounced, earthy, slightly smoky flavour with a distinct hint of bitterness, but no acidity. It is a roast that is often used in blends intended for strong coffees such as ristretto. There are several types of very dark roast, such as: High, Continental, New Orleans, European, Espresso, Viennese, Italian and French.

Coffee roasting is important in the context of preparing an aromatic, full-flavoured beverage. In the process, it is not only the degree of roasting that is important, but also the selection of the right beans, the roasting process and the time that has passed since the beans were roasted. In order to ensure that the coffee’s taste and aroma are fully released, it is worth betting on reliable suppliers, such as Foodcom S.A., which offers selected coffees from all over the world.